- IOS XR
IOS XR is the latest train of
Cisco Systems ' widely deployed Internetworking Operating System (IOS), used on their high-end carrier-graderouter s such as theCRS-1 and the 12000 series.Architecture
According to Cisco's product literature, IOS XR shares very little infrastructure with the other IOS trains, and is instead built upon a "preemptive, memory protected,
multitasking , microkernel-basedoperating system ". [ [http://www.cisco.com/en/US/products/ps5845/prod_qandas_list.html Cisco IOS XR product literature] ] The microkernel is provided byQNX . [ [http://www.qnx.com/news/pr_1329_3.html QNX press release] confirming use of their microkernel in IOS XR]IOS XR aims to provide the following advantages over the earlier IOS trains:
* Improved
high availability (largely through support for hardware redundancy and fault containment methods such as protected memory spaces for individual processes and process restartability)
* Better scalability for large hardware configurations (through a distributed software infrastructure and a two-stage forwarding architecture)
* A package based software distribution model (allowing optional features such as multicast routing andMPLS to be installed and removed while the router is in service)
* The ability to install package upgrades and patches (potentially while the router remains in service)
* A web-based GUI for system management (making use of a generic,XML management interface)History
IOS XR was announced along with the CRS-1 in May 2004. [ [http://newsroom.cisco.com/dlls/2004/prod_052504.html?CMP=ILC-001 Cisco press release] announcing CRS-1 and IOS XR] The first generally available version was 2.0; the first version generally available for the 12000 router series was 3.2. The most recent release is version 3.7, released in June 2008. [ [http://www.cisco.com/en/US/products/ps5845/prod_release_notes_list.html Cisco's release notes] for the various IOS XR versions]
References
External links
* [http://www.cisco.com/en/US/products/ps5763/products_visual_documentation.html Cisco multimedia documentation] covering IOS XR and its supported systems
* [http://www.qnxzone.com/?q=node/view/131 Cisco reveals it uses QNX] to power its IOS XR software
* [http://www.cisco.com/en/US/products/products_security_advisories_listing.html Cisco Security Advisories] - complete history
* [http://www.cisco.com/web/Cisco_IOS_XR_Software/index.html Cisco IOS XR Software General Information]
* [http://www.uknof.org.uk/uknof11/Nisbet+Wilson-HEAnet.pdf HEAnet's New Network and Working with IOS-XR]
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